Cardiac devices may need more rigorous testing before FDA approval
Research that included a review of 80 cardiac devices shows that FDA approval of the devices followed a single study. The findings suggest that high quality studies are needed prior to pre-market approval (PMA) of cardiac devices that include pacemakers, implantable cardiac defibrillators and stents.
The study is published December 23/30 in JAMA. The authors reviewed studies used by the FDA presented by the manufacturers of cardiac devices when seeking approval or their use. The researchers found that sixty five percent of devices received pre-market approval by the FDA from a single study, based on 123 reviews.
The findings come from Sanket S. Dhruva, M.D., of the University of California, San Francisco, and colleagues who say, "Ideally, this evidence should consist of randomized, double-blinded studies with adequate controls, sufficient duration, and thorough follow-up on prespecified primary end points without bias."
Of the 123 cardiac device studies analyzed, using summaries of safety and effectiveness data (SSEDs), the researchers also found that only 98 reported the number of individuals enrolled in the study, and that in 113 studies, more participants were enrolled than were analyzed, a factor that could result in study bias
"In the SSEDs, there were 157 primary end points for which both the number enrolled and analyzed were stated. Of these, 122 (78 percent) had a discrepancy between the number enrolled and those analyzed," the authors write. The authors also found that end points for studies reviewed by the FDA for cardiac device approval were also suboptimal – of 213 endpoints, fifteen percent were not interpretable.
The authors write, "The emphasis at the FDA in the last 17 years since the Prescription Drug User Fee Act has been rapid approval of new drugs. This study suggests that the emphasis for the FDA in 2009 and beyond must be approvals based on research that meets rigorous scientific standards for evidence of benefit and lack of harm to patients. To uphold the FDA's mission of ensuring 'safe and effective' medical devices, it is essential that high-quality studies and data are available."
It may be that the FDA is new at approving devices, a factor the authors say might could be responsible for cardiac devices being passed by the FDA without high quality studies. “First, device approvals are a more recent activity for the FDA, having begun in 1976 with the FDA Device Amendment, so the agency has less experience with devices than it does with drugs. Further, the last decade has brought a significant increase in the number and complexity of devices. The number of cardiac devices used in 2008 include, at least 350,000 pacemakers, 140,000 implantable defibrillators, and 1,230,000 stents.
The authors also said the findings are based on safety and effectiveness data (SSEDs), and some information could be missing. However cardiac device studies “should be a thorough and accurate compilation of the FDA's critique of evidence." The analysis suggests that FDA approval of cardiac devices should follow more rigorous testing, with clear endpoints, and accuracy regarding the number of study participants and individuals analyzed, to ensure that medical devices are "safe and effective".